Seattle voters should pass Proposition No. 1, providing $290 million to replace the Seattle seawall, a 100-year-old, deteriorating structure that is vital to the safety and economic life of the region.

Rebuilding the Seattle seawall is like repairing the foundation of a house: Once finished there is little visible evidence of the work and expense that went into the project. But if the work is neglected and the house falls down, all can see that the work should have been done.

Right now what is holding up the Seattle waterfront and protecting it from storm damage is a structure of steel, concrete and timbers built between 1916 and 1934. The timbers have been nibbled away by gribbles and other marine borers. The structure has been buffeted by tidal action, and water has sloshed inside it, leaving voids where there should be support.

A repeat of the 2001 Nisqually earthquake would be all the evidence anyone needs to see that work should have been done.

Voters in the Nov. 6 election can make sure this work gets done by approving a 30-year bond levy to raise $290 million to replace the seawall for another 100 years. The measure would cost the owner of a $360,000 home (the median price in Seattle) about $59 a year.

Besides replacing the seawall between South Washington and Virginia streets, the project includes restoration of city-owned piers that are in such bad shape the city has been forced to limit their public use.

The rebuilt seawall would not be entirely a vertical wall. Plans include horizontal shelving to provide better salmon habitat and some public access to the water.

Engineers predict that even without an earthquake, parts of the seawall could fail, threatening to disrupt rail service and highway travel, now estimated at 110,000 vehicles daily. The entire region would be disrupted if natural gas, telecommunications, water, power and sewer lines protected by the seawall ruptured.

Now is the time to get this work done. The machine boring the tunnel that will replace the Alaskan Way Viaduct will pass within 30 feet of the seawall in late 2013, opening up space to work on the wall. Furthermore, the seawall will serve as the foundation for waterfront improvements planned after the viaduct is removed.